Cryogenic Characteristics of InGaAs MOSFET

We present an investigation of the temperature dependence of the current characteristic of a long-channel InGaAs quantum well MOSFET. A model is developed, which includes the effects of band tail states, electron concentration-dependent mobility, and interface trap density to accurately explain the measured data over all modes of operation. The increased effect of remote impurity scattering is associated with mobility degradation in the subthreshold region. The device has been characterized down to 13 K, with a minimum inverse subthreshold slope of 8 mV/dec and a maximum ON-state mobility of 6700 cm /V s and with values of 75 mV/dec and 3000 cm /V s at room temperature.